Devices that receive signals from Global Positioning System (GPS) satellites are generally available to members of the public. Though useful for telling the individual holding the unit where on Earth the individual is, these GPS receivers do not typically transmit the location of the individual. Thus the coordinates are useful to the individual, but not to someone that wants to find the individual.
Systems used by the armed forces for transporting goods, supplies, and materials (logistic systems) may have access to radio transmitters to report the location of vehicles and/or units to headquarters. When manually coupled with a GPS receiver, an individual in a unit can inform headquarters of his or her position via verbally relaying the coordinates via radio.
Likewise, corporations may have similar systems in place to track cargo transports, e.g., reporting location information to a corporate operations center, or they may utilize point-of-reception reporting, i.e., updating the location of a good or supply when the item is processed by an intermediate facility.
An obstacle to efficient utilization of these technologies is the size of the components of the communication system and the awkwardness of manual combination of the components by an operator. These technologies lack a unified arrangement that maximizes the efficiency of the technology while simultaneously minimizing the footprint of the system.